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Executive Summary This project was initiated as a feasibility study to determine if channel catfish abundance in the lower Yampa River could be reduced through mechanical removal. The study area on the Yampa River extended from the upstream reach of Yampa Canyon to Laddie Park. The river was stratified into 4 longitudinal reaches. Each individual longitudinal reach was subdivided into two reaches, in which one of the two was randomly designated as a removal (treatment) reach. The remaining reach was designated as a control reach. Channel catfish were removed from treatment reaches during multiple passes during 1998 and 1999. Catfish were not removed from control reaches until the last pass of each season to allow comparison of relative densities between treatment (removal) and control (non-removal) reaches.. In a comparison of several methodologies, angling was determined to be the most effective method of removing channel catfish. Although other methods were more effective per hour of effort, more fish could be removed per trip by angling, particularly when volunteer help was provided. During both years, 4,256 channel catfish were removed from the Yampa River. Although this number was much fewer than removed by earlier studies on the Green and San Juan rivers, comparison of treatment with control catch rates suggested that the channel catfish population in three of the four reaches had been significantly reduced. Regression analysis indicated that channel catfish densities in the Yampa River were much less than reported in the San Juan River, but similar to those reported in the Yampa River upstream of the study area. The condition of channel catfish was relatively low suggesting that the carrying capacity may not be as high as other rivers. A pattern in length frequency was apparent in that average size of channel VI